Ramakrishnan, C. ; Ramachandran, G. N. (1965) Stereochemical criteria for polypeptide and protein chain conformations. II. Allowed conformations for a pair of peptide units Biophysical Journal, 5 (6). pp. 909-933. ISSN 0006-3495
![]()
|
PDF
- Publisher Version
1MB |
Official URL: http://linkinghub.elsevier.com/retrieve/pii/S00063...
Related URL: http://dx.doi.org/10.1016/S0006-3495(65)86759-5
Abstract
The conformation of a polypeptide or protein chain may be specified by stating the orientations of the two linked peptide residues at each alpha carbon atom in the chain, namely the two dihedral angles ϕ, ϕ' about the single bonds N—αC and αC—C' from a defined standard conformation. By using certain criteria of minimum contact distances between the various atoms, the allowed angles of (ϕ, ϕ') have been worked out for three values of the angle N-αC-C' (τ), namely 105, 110, and 115° for non-glycyl, and 110 and 115° for glycyl residues. The theory is compared with all the available crystallographic data (up to early 1965) on simple (di- and tri-) peptides, cyclic peptides, polypeptide and protein structures, and the observed data fully support the conclusions from theory. The effect of the gamma carbon atom, in its three possible positions, is also discussed, and is found to alter the outer limits of the allowed region of (ϕ, ϕ') only slightly. The paper contains exhaustive references to the published data on these structures, using X-ray diffraction.
Item Type: | Article |
---|---|
Source: | Copyright of this article belongs to Biophysical Society. |
ID Code: | 33717 |
Deposited On: | 01 Apr 2011 13:24 |
Last Modified: | 17 May 2016 16:36 |
Repository Staff Only: item control page